1. Fields of the Invention
The invention relates to an oval-tracked exercise apparatus, and more particularly, to an exercise apparatus in which the oval track movement is adjustable to allow the simulation of walking exercise in an uphill or a downhill position.
2. Description of the Related Art
A conventional oval-tracked exercise apparatus includes a main body consisting of an upright frame and a base frame both of which are connected to each other. Two planks each have one end pivotally connected with a corresponding handlebar and the other end connected with a crank to create an alternating movement. In treading treadles on the planks, an oval track movement can be simulated for the purpose of taking a jogging exercise
In order to facilitate the swing movement of the operator's hands during the exercise session, handlebars are provided for simulating the walking action. As shown in FIG. 5, TW 86218424 teaches an oval-tracked exercise apparatus that includes a main body consisting of a lower frame A01 and an upper frame A02. The upper frame A02 and an auxiliary frame A03 are attached to a cross bar A21. A front upright tube A23 is pivotally connected to each end of the cross bar A21. Moreover, a connecting rod A12 with one treadle A11 is pivotally connected to the bottom end of the hanging tubes A23. The bottom end of each treadle A11 is positioned on a crank A14 of a flywheel A13 rotatably mounted on the lower frame A01. In this way, an oval exercise tract can be simulated for an up-and-down movement in alternating succession. A handlebar A22 is received within each of the front upright tubes A23; meanwhile, its length is adjustable according to the height of the operator. The handlebars A22 can be gripped by the operator's hands during the exercise session to keep his balance.
Moreover, another oval-tracked exercise apparatus has been developed for simulating a walking exercise in uphill or downhill position. As shown in FIG. 6, TW 86218424 teaches an oval-tracked exercise apparatus that includes a main frame consisting of an upright frame B01 and a base frame B02. A handlebar B22 is pivotally connected to the right and the left side of the upright frame B01. Meanwhile, the hanging handlebars B22 are pivotally attached to the adjusting rods B21 and the connecting rods B12 with treadles B11. The distal end of the adjusting rods B21 is in connection with the slide rod B23 while the front end of the slide rod B23 is mounted on cranks B14 of a flywheel B13 rotatably fitted to the base frame B02. In addition, rollers B24 are slid ably mounted on the base frame B02. The angle of the slide rod B23 is adjustable by the adjusting rods B21 on the handlebars B22. In this way, the walking exercise in uphill or downhill position can be indirectly simulated due to the change of the angle when the treadles B11 move on the slide rod B23 in an oval exercise track.
As shown in FIG. 7, TW 92220374 teaches still another oval-tracked exercise apparatus that includes a main frame consisting of an upright frame C01 and a base frame C02. A handlebar C22 is pivotally connected to the right and the left side of the upright frame C01 in a hanging state. One end of two planks C12 is adjustably attached to the corresponding handlebar C22 while the other end thereof is mounted on cranks C14 of a flywheel C13 rotatably attached to the base frame C02. In treading the planks C12, both planks C12 will move up and down in alternating succession under the influence of the crank C14, thereby simulating an oval walking track. Also, the uphill and the downhill walking state can be synchronically simulated by adjusting the position of the adjusting member C21 on the handlebar C22.
From the above-mentioned development of the oval-tracked exercise apparatus, we may find a common drawback that an adjustment along the handlebar must be carried out to achieve a desired walking exercise in uphill or downhill position. In this way, the right and the left handlebar each have to be carefully adjusted in changing the walking exercise in uphill or downhill position for achieving the balance sense during the exercise session. This wastes, however, much time and effort.